6431406249581 has 2 divisors, whose sum is σ = 6431406249582. Its totient is φ = 6431406249580.

The previous prime is 6431406249559. The next prime is 6431406249607. The reversal of 6431406249581 is 1859426041346.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 5932468863556 + 498937386025 = 2435666^2 + 706355^2 .

It is a cyclic number.

It is not a de Polignac number, because 6431406249581 - 2²² = 6431402055277 is a prime.

It is a super-2 number, since 2×6431406249581² (a number of 26 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6431406249181) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3215703124790 + 3215703124791.

It is an arithmetic number, because the mean of its divisors is an integer number (3215703124791).

Almost surely, 2^{6431406249581} is an apocalyptic number.

It is an amenable number.

6431406249581 is a deficient number, since it is larger than the sum of its proper divisors (1).

6431406249581 is an equidigital number, since it uses as much as digits as its factorization.

6431406249581 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4976640, while the sum is 53.

The spelling of 6431406249581 in words is "six trillion, four hundred thirty-one billion, four hundred six million, two hundred forty-nine thousand, five hundred eighty-one".